The overall objectives of this research project are to develop a novel method (1) to chemically crosslink binding proteins (ligands) such as lectins, peptide hormones, toxins, and antibodies to their specific receptors in membranes, and (2) to identify the receptors molecules. We have synthesized a family of cleavable photosensitive reagents which have been characterized by thin layer chromatography and infra red and nuclear magnetic resonance spectroscopy (both proton and C13). The intermediates of the synthesis have also been characterized by thin layer and gas liquid chromatography, infra red and nuclear magnetic resonance spectroscopy and mass spectrometry.